Deep Foundations Institute DFI ® 326 Lafayette Avenue Hawthorne, NJ 07506 USA Phone: +1 (973) 423-4030 +1 (973) 423-4031 Fax: Expansion of Big Sky Resort in Montana required excavation, blasting, rock scaling, micropiles, tiebacks and more at elevations of approximately 14,000 ft (4,300 m) and required helicopter support.